Table 2.

Proteins predicted to bind purines and analyzed in this study

Name	Ref. Seq ID	Receptor typea	Motif variantb	Species/strain	Phylogenetic category (Phylum)	Pathogenicity/characteristicsc
R1	WP_219614703	CR	YRWFN	Aeromonas salmonicida	Pseudomonadota	Fish pathogen, mainly salmon. Important economic losses
R2	WP_107944080	CR	YKWYN	Campylobacter concisus	Campylobacterota	Human pathogen, causes inflammatory bowel disease
R3	WP_124259872	CR	YRWFD	Burkholderia vietnamiensis	Pseudomonadota	Human pathogen, causes lung infections. High mortality rate
R4	WP_199478134	CR	FRFYN	Marinomonas spartinae	Pseudomonadota	Halophyte plant isolate, can promote plant growth
R5	WP_131005693	GGDEF/EAL	YRWFN	Clostridioides difficile	Bacillota	Human pathogen, at times fatal. Disrupts gut microbiota
R6	WP_185834821	GGDEF	YKWFN	Vibrio cholerae	Pseudomonadota	Human pathogen, causes life-threatening diarrheal disease
R7	WP_038903150	GGDEF	YHWFN	Dickeya zeae	Pseudomonadota	Plant pathogen, in particular maize and rice
R8	WP_227113344	GGDEF	YRWFN	Eggerthella sinensis	Actinomycetota	Human pathogen, causes life-threatening bacteremia
R9	WP_198537540	GGDEF	YKWFN	Vulcanococcus limneticus	Cyanobacteriota	N2-fixing bacterium, isolated from freshwater
R10	WP_110129388	HK	YKWFN	Coraliomargarita sinensis	Verrucomicrobiota	Isolated from a marine saltern
R11	WP_162024566	HK	YKWFN	Lentimonas sp. CC4	Verrucomicrobiota	Efficient degrader of fucoidan, a major algae product
R12	WP_220621668	HK	YKWFN	Ruficoccus sp. ZRK36	Verrucomicrobiota	Isolated from deep sea cold seep
R13	WP_167859577	S/T phos	YKWFN	Paenibacillus cymbidii	Bacillota	N2-fixing isolated from orchid roots
R14	WP_021170906	S/T phos	YKWFN	Sporomusa ovata	Bacillota	Anaerobic, endospore forming bacterium, isolated from leaves
R15	WP_207952809	S/T phos	YRWFN	Paenibacillus sp. S3N08	Bacillota	Isolated from agricultural soil

The first column specifies the number given to the different receptors.

^aCR chemoreceptor, GGDEF/EAL diguanylate cyclase/phosphodiesterase, HK histidine kinase, S/T phos serine/threonine phosphatase.

^bLigand binding residues of the dCache_1PU motif are shown. Strands of non-conserved residues between the motif residues are implied according to the motif definition in Fig. 2D.

^cThe corresponding references are provided in Supplementary Table 2.